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CVE-2026-25905 Detail

Description

The Python code being run by 'runPython' or 'runPythonAsync' is not isolated from the rest of the JS code, allowing any Python code to use the Pyodide APIs to modify the JS environment. This may result in an attacker hijacking the MCP server - for malicious purposes including MCP tool shadowing. Note - the "mcp-run-python" project is archived and unlikely to receive a fix.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://research.jfrog.com/vulnerabilities/mcp-run-python-lack-of-isolation-mcp-takeover-jfsa-2026-001653030/ JFrog

Weakness Enumeration

CWE-ID CWE Name Source
CWE-653 Improper Isolation or Compartmentalization JFrog  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-25905
NVD Published Date:
02/09/2026
NVD Last Modified:
02/09/2026
Source:
JFrog